What is Triplicity Rulers?
The triplicity system assigns planetary rulers to each of the four elements. Fire signs (Aries, Leo, Sagittarius) have Sun as day ruler and Jupiter as night ruler. Earth signs have Venus (day) and Moon (night). Air signs have Saturn (day) and Mercury (night). Water signs have Mars (day) and Moon (night). A planet in its own triplicity gains a moderate essential dignity, stronger than term or face but weaker than domicile or exaltation. Sect dependence makes this dignity dynamic between day and night charts.